Fan construction



Patented Apr. 3, 1941 FAN CONSTRUCTION Abe 0. Samucls, Rochester, N. Y., assignor, by mcsne assignments, to Seaboard Commerc al Corporation, New York, N. Y., a corporation of Delaware Application November 9, 1937, Serial No. 173,662

(Ci. 230-l34) 2 Claims.

in electric and other fans of the centrifugal type in which the blades are arranged substan tially parallel to the axis of rotation, the blades have heretoztore been made of substantially unyielding metal or other rigid materia1 which could not yield if any object were intruded into the path of such blade but would damage or destroy such object. Metal blades are furthermore subject to chemical corrosion which gradually destroys them, especially when the fan is operated to canry oii vapors or gases containing chemicals which either cause corrosion or set up electrolysis in the metal blades.

My present invention relates to such fans and has tor one of its objects to provide a fan of this type with flexible fan blades of suitable material and shape to give the blades stability for an eiilcient operation of the fan, combined with sulidoient flexibility to cause any portion of the moving blades to yield when a stationary rig-id or semi-rigid member is brought in contact with them, and to be self restoring to normal position when the intruded member is withdrawn.

it iurtherobject of this invention is to provide a tan at this type with blades made of non-metalits material so as to make them non-corrosive and resistant to the chemical action and electroly-sis.

ltd'l these and other objects and attendant advantages will become more readily apparent from i the detailed description of several embodiments or the invention which follows, reference being bad to the accompanying drawings in which Figure l is a side elevation of a conventional term oi centrifugal fan.

Fi e 2 is a cross section thereof taken on the line tit- W3? of Figure 1.

Figure 3 is a detail perspective and sectional view of one form of my novel blade and its mounting as used for the rotor of the centrifugal fan.

Figure 4 is a detail perspective view and section of modified form of my novel blade and its mounting.

Figure 5 is a. detail perspective view of still another modified form of my novel blade and its mounting;

Figure 6 shows a sectional view of a modified form of a centrifugal fan provided with my novel blades as it appears mounted to a fan motor.

Figure '7 is a front elevation of the fan illustrated in Figure 6.

in the figures reference numeral l indicates the motor of a centrifugal fan which is mounted to rotate in the housing 2. The intake opening 3 of the housing is located in the side of the housing axially in line with the hollow center of the rotor and the exhaust. The outlet opening t of the housing is located at on end of the housing substantially tangential to the rotor. The action of the rotor causes air or gases to enter the in take opening 3 into the hollow center thereof and be expelled .therefrom and forced out of the out let 4 in the casing by the radially arranged fan blades 5 of the rotor.

The fan blades 5 are made of suitable nonmetallic material and shap so that when mounted they will have stability for an efiicicnt displacement of air or gases in the operation of the fan, combined With sufilcient flexibility to cause any portion of the moving blades to yield when a stationary rigid or semi-rigid member is brought in contact with them, and to be selfres-toring to normal position when the contactme member is withdrawn. Rubber or fabric or a combination of the two have been found to be suitable material for the blades especially in view of the fact that this material is substantially honcor-rosive and resistant to the chemical action to which metal blades of a fan are usually subjected.

In Figure 3 I have illustrated one form of mounting for such blades in which the rotor is provided with a plurality of curved. mounting ribs 6 which are slotted with an outwardly tapering slot 'i. The blades 5 are inserted into these slots so as to be curvedly held in place therein to give the otherwise flexible bIades suffircient stability for the displacement of air on the rotation of the fan. The blades, as shown in Figure 3, may have a tapering cross section which will increase the stability of the blade.

In Figure 4 l have shown a similar blade with a simplified mounting in which the base of the blade is vulcanized or otherwise suitably fastened to one side of the curved rib B.

In the modification illustrated in Figure 5, the flexible blade comprises a substantially thin sheet member 9 which is anchored to the spaced posts II], In carried by the rotor and held stretched between them.

In Figures 6 and 7 the rotor comprises the spider member H which is keyed to the armature shaft I2 of the motor [3. concentrically grouped on the spider and axially extending from it are the curved supporting arms l4, M which are provided with the dovetailed shaped slots IE to receiv the dovetailed base edges it of the flexible blades I1 and hold these blades curved in a radial position.

I claim:

1. A fan comprising a rotor, substantially ax- 2 apa'moi rled by said rotor and held uniformly spaced radlanyi romthooenterotmbationoftherowr atoneendthereoLatlexiblebladeheld clamped withipabosebebweeneochpairotribstopmvide yielding walls for the unobstructed passage otdrtmmtheinsldeottherotortotheoumde thereof.

ABE O. SAMUEL-S. 

